Automatic lathe feed mechanism



Nov. 22, 1949 H. J. SIEKMANN ET AL AUTOMATIC LATHE FEED MECHANISM FiledOct. 25, 1946 5 Shets-Sheet l INVENTORS. HAROLD J. SlE/(MAN/V 'ANDHARRYC. KEMPER A TT'ORNEYS.

Nov. 22, 1949 H. J. SIEKMANN ET AL AUTOMATIC LATHE FEED MECHANISM 5Sheets-Sheet 2 Filed Oct. 25, l94.6

' INVENTORS.

HAROLD .LSIEKMANN HARRY C. KEMPER ATTORNEYS. v

Nov. 22, 1949 H. J. SIEKMANN ET AL AUTOMATIC LATHE FEED MECHANISM Filed001;. 25, 1946 5 Sheets-Sheet 3 INVENTORS. HAROLD J. SIEKMAN/V HA/PR) 0.KEMPER ATTORNEYS.

Nov. 22, 1949 H. J. SIEKMANN ET AL 2,489,203

AUTOMATIC LATHE FEED MECHANISM Filed Oct. 25, 1946 5 Sheets-Sheet 5 TRaTF c a RCRb 6 Q Q FIG? INVENTORS.

Q Q HAROLD J. S/IEKMANN 15 1 ANDHARR) C. KEMPER isms M A T TORNEY.

Patented Nov. 22, 1949 AUTOMATIC LATHE FEED -MECHANISM Harold J.'Siekmann, Cincinnati, and Harry C. Kemper; Goshen Township, ClermontCounty, Ohioyassig-nors toThe R. K. Le Blond Machine Tool iCo.,.Cincinnati, Ohio, a corporation of Delaware Application October 25,1946, Serial No. 705,640

10 .Claims.

This invention pertains to machine tools and is particularly directed toimprovements in automatic lathe mechanism.

One of'the objects 'of this invention is to provide an improved feedtransmissionmechanism for actuating the tool slides of "an automaticlathe.

Another object of this invention isto provide an improved feedtransmission for'an automatic lathe which is adaptable to quick set upand accuracy and simplicity'of control to meet 'a'large variety ofworking conditions.

Another objectof this invention is toaprovide an improved electriccontrol mechanism for the feed mechanism of an automatic lathe.

It is also an object of this invention to provide a simple and effectivemeans for providin sequential delayed control of the longitudinalmovement of the tool s'lidein relation .to the cross feed movementthereof And a still further object of this invention is to provide animproved feedand rapid traverse operating mechanismjfor a camdrum-controlled tool feeding mechanism, including a :lost motionarrangement for efiecting .a. delayed sequential series of. movementsbetweenthe longitudinal and cross feed movements of the tool slide.

It is alsothe purpose of this inventiontoprovide a novel and improvedelectrical control mechanism for .an automatic lathesfeed meche anism.

Further features and. advantages of this .invention will. appear from :a:detailed description of the drawings .in. which:

Figure 1 isa front elevationshowing an automatic lathe incorporatingtheteatures of this.

invention.

Figure 2 is a left-hand end elevation of the automatic lathe shown inFigurel.

Figure 3 is a right-hand end elevation of the automatic lathe shown inFigure vl.

Figure 4 is an enlarged fragmentary. transverse section throughtheautomatic lathe on the line 4-4 of Figure 1.

Figure 5 is a fragmentary enlarged section through the cam drummechanism of the front carriage indicated by the line 55 -in Figured.

Figure 6 is a diagrammatic layout of the power transmission gear-ingotthe .lathefeedand rapid traversemechanism.

Figure 7 is a wiring diagram of theelec'tric control mechanism for theautomatic lathe.

Figure 8 is a view of the front and rear push button control stations'forthe machine.

For illustrative purposes, this invention is shown applied to anautomatic lathe havinga bed l-li mounted on suitable supporting legs "Hand [2. The head stock l3, containing *the work spindle I4 and center I5, is appropriately fixed to the bed l0. Atail stock-l 6 is suitablyad-justably mounted on the guideway surfaces l1 and I801 the 'bed andclamped in any desired longitudinal position therealong by suitableclamping nuts [9.

Mounted to slide longitudinally on the guideways ll and 20 is the fronttool carriage 2!. A rear tool carriage 22 is arranged to slidelongitudinally of the bed on the guideways 23 and 24. On the front toolcarriage is mounted the cross slide 25 on suitable guideways 26 andcontains 'an appropriate tool block 21 carrying the front cutting tools28. The rear tool carriage 22 is provided with a cross slide 29 mountedonsuitable guideways 30 on the rear carriage 22 and 'upon which ismounted a suitable tool block 3| shaft 40 of the head stock transmissionby'plac- .ing change gears at 41 and 42, while at another time. changegears may be placed at 4! and 43 to interconnect drive from the shaft 39"to a shaft 44.

When the shaft 40 is being driven, its gear 45 drives continuously, alarger gear 46 of the compound gear 46-4! mounted on a shaft 48. in

the head stock 1.3. The gear 46-41 may be .shiftedby operating lever45a, Figure 1, so at .one time to connect the gear tltwith the gear 49fixed on the lathesp'indle Hi4 While at another time for shifting thegear d! into engagement with a gear .50 fixed on the spindle. When theshaft 39 is connected to the change gears 4'! 43 to drive the shaft 44,a. chain sprocket gear 5| fixed on the shaft 44 and driving throughthechain 52 applies .power to the chain sprocket gear Ettmouritedon .thework spindle l4. Thusthree ranges of change .gear drive may be effectedto the spindle l4 coupled with the change effected by the shifting ofthe gear 46-4l so that there is provided a variable or change speedtransmission. for rotatin the workspindle at any desired cutting speed.

The feed drive power take-01f for actuating the gear I3 to be drivenfrom the shaft l0.

the tool carriages and slides is derived from a gear 54 fixed on thework spindle I4 and connected to drive a gear 55 on a shaft 56 to whichis fixed the gear 5?. The gear 51 is connected to drive a gear 58rotatably journaled on the feed output shaft 59 of the head stock. Theshaft 59 is formed with a splined portion 59a on which is drivinglymounted the feed disconnect clutch spool 60 having clutch teeth 6|adapted to engage clutch teeth 62 formed on the gear 58. An output gear63 fixed to the shaft 59 serves as one confining abutment for thecompression spring 8% which engages the spool 69 so as to normallymaintain the clutch teeth BI and 62 in feed driving engagement from thespindle I4 to the gear 63. A feed clutch solenoid FCS has its armature85 connected through a suitable link 60 and the lever til so that whenenergized it releases the clutch spool 50 from the gear 58 bycompressing the spring 64 and when deenergized the solenoid FCS allowsthe spring 64 to automatically reconnect the feed clutch spool 60 withthe gear 58.

Driving power from the gear 63 is conveyed to the gear 68 and throughthe shaft 69 to the change gears l at the left hand end of the lathehead stock end of the bed. Power then passes through the shaft H to agear I2 which is connected to a gear l3 through an idler gear I4. Thegear I3 is formed on the outside driving ring of an overrunning clutch Iwhich is so arranged that the gear 713 may drive the shaft "I6 in theforward feed direction but that rotation of the shaft it at a more rapidrate than the rate of rotation of the gear l3 will not cause Thusforward feed driving power is applied to the shaft I5 through theoverrunning clutch I5.

Rapid traverse driving power is applied to the shaft I6 from areversible rapid traverse drive motor I? having a gear 38 connected todrive a gear I9 fixed to the shaft it. A zero speed switch 80 isconnected through a gear 8| also to be driven from the gear I9. Thuswhenever the rapid traverse motor fl is energized in the forwarddirection, shaft '65 may overrun or rotate at a more rapid rate than theoverrunning clutch I5 and the gear "173 being operated at feeding ratefrom the headstock spindle I4. When it is desired to reverse the rapidtraverse movement, solenoid P08 is energized to release the .clutchspool 80 from the gear 58 so that the rapid traverse motor will not haveto drive the lathe transmission back through the overrunning clutch I5and the high speed-up drive gearing necessary to provide proper feedrate drive from the spindle It to the shaft I0. Thus the rapid traversemotor I! may be reversibly operated for effecting rapid traversemovements to the tool carriages and slides in either direction.

Driving power from the shaft 16 is transmitted from the gear 82 fixed onthe shaft to a gear 83 fixed on the shaft 841 which in turn has fixed onit a gear 85 driving a gear 86 fixed on the drive shaft 81 journaled onthe bed of the lathe in any suitable manner and having an elongatedsplined portion 83 extending longitudinally along the front of the lathebed. The splined portion 88 projects into a mating driving splined borein the driving gear 89 which is journaled against axial rotation in thefront carriage 2I. An idler shaft 90 suitably journaled in the carriage2| has a gear 9i driven from the gear 89 and a gear 92 fixed to it whichdrives the cam drum gear 93 carried on the cam drum shaft 94 suitablyjournaled against axial movement in the carriage 2I in bearings 95 and96, Figure 5.

Fixed to rotate with the shaft 94 are the cam drums 91 and 98. The camdrum 91 has a cam slot 99 for effecting the longitudinal movement of thecarriage along the bed I 0, while the cam drum 98 has a cam surface I00for effecting the cross slide movement of the slide 25. Cooperating withthe cam slot 99 in the cam drum is a cam roller IOI which is fixed on acam bar I02 arranged to slide longitudinally of the bed in suitableguideways I03 formed in the bed I0, as best seen in Figures 4 and 5. Anadjustable abutment and dwell block I 04, adjustably held in place bysuitable screws I05 to the bed I0, has abutment surfaces I04a and I04bcooperatively engaging with the surfaces I02a and I02b formed by theslot I06 in the bar I 02. B proportioning the space between the surfacesI04a and I04b relative to the width of the slot determined by thesurfaces I02a and I022), a predetermined relative motion of the bar I02with respect to the bed may be obtained.

The purpose of this lost motion arrangement between the block I04 andthe bar I02 is to provide an initial dwell or nonmovement .period forthe carriage 2| during a continuous movement of the rotation of theshaft 94. Thus, as the shaft 94 and cam drum 91 initially rotate, thebar I02 will be moved from position shown in Figure 5, without movementof the carriage along the bed, until the surface l02a engages thesurface I04a, whereupon the cam drum reacting with the roller IOI willthen cause longitudinal movement of the carriage 2I.

During the period of nonmovement of the carriage as the surface I82aapproaches the surface I04a, the cam drum 98 may operate with its camsurface I90 engaging the cam plate roller I 01 on the cam plate I08mounted in suitable guideways I09 for longitudinal sliding movement inthe carriage ZI. The portion of the cam plate I08 is formed with asuitable cam slot H0 in which operates a cam roller III, the cam rollerI I I journaled on a stud II 2 fixed to the bottom slide II3 of thecross slide 25. A suitable cross slide adjusting screw H4, Figure 4,journaled against axial movement on the cross slide 25 and operating ina nut II5 fixed to the bottom slide I I3 servesto provide accurate finaladjustment of the cross slide and cutting tools 28 for proper sizing ofthe Work piece.

Thus, upon rotation of the cam drum 98, the

cam plate I08 is moved so that the cross slide 25 can be moved toward orfrom the work. This ing, or after movement of the carriage along the bedby the relative relationship of the block I04 in the slot Hi6 and theconfiguration of the cam drum slots in the cam drums 97 and 98. Thus,for example, the cam drum might be rotated at rapid traverse movement byenergizing the rapid traverse motor ll during which time the bar I02would be taking up lost motion under the influence of the cam drum 9'!while the cam drum would be initially moving the tools 28 radially intodesired cutting position. At the time this position was reached, thesurface I02a of the bar I02 would then come into engagement with thesurface Ill la of the block I04 fixed on the bed so as to begin thelongitudinal movement upon further rotation of the shaft 94. At thistime also it might be desirable to drop the rotation speed of the shaft9G down to feeding speed by de-energizing the motor 11 and allowing thefeed drive aesaaos through the overrunning clutch. :145. to :now takeover rotational control of the :cam drumsBI and $98. After the carriage2I1has traveled the full length :of its longitudinal movement as determined by the shape of the cam slot 199, theslot may then reverse "its"direction of helix whereupon the carriagewould be left :stran'de'din:dwell position to cease its longitudinal movement since the bar I02would then beginmovingzinuthe opposite direction with the surface I04bmoving toward the surface I821) and during which time the cam drum 98continues to rotate to withdraw the tools 28 radially outwardly tocomplete, for example, a facing out on the work. After the surface 1 94bengages the surface I02b, the carriage would then again, under theinfluence of the cam drum 9?, return backward longitudinally of the bedto initial starting position to begin another cutting cycle.

Thus, there is provided amechanism whereby a continuous drive to the camdrum at rapid traverse or feed may effect a delayed application of thelongitudinal feed movement while initially positioning the cutting toolsin cross movement and then automatically pickingup the longitudinal feedmovement and again bringing it to a stop while allowing thecutting toolsto feed radially outwardly, after which automatically beginning againthe return longitudinal movement of the carriage, all of said movementsbeing accomplished with a single continuous direction of rotation of camdrum mechanism.

The rear carriage 22 is operable similarly to that of the front carriagejust described in detail and suffice it to indicate that the power tothe rear carriage is derived from a chain sprocket gear I I6 fixed onthe shaft 81 and having a chain drive III extending to the rear of thelathe bed to engage the chain sprocket II8 fixed on the rear drive shaftI I9. This shaft -II9 has a splined portion I20 extending longitudinallyof the rear portion of the bed as in the case of the-drive shaft portion88 of shaft 81. A splined bore gear I2I slidingly engaging in drivingrelationship on the splined portion I29 drives an idler gear I 22mounted on an idler shaft I22a'which is journaled in the rear carriage22 and carries a second gear 12212 which engages with the cam drum drivegear I23 mounted on the cam drum shaft I23a carrying the rear cam drumsI24 and I25. A similar lost motion connection-to thatof the frontcarriage is provided between the "longitudinal feed bar I26 slidablymounted in guidewa-ys I 21 along the rear of the bed and connected to beactuated from the cam drum I24 through the cam roller I28 andslot I29.similar lost motion connection is provided by the block I39 and slotI3lla to that of the block I04 and slot I06 shown in Figure 5.

A cam slot I3I in the cam drum I25 actuates the cam roller I32 connectedto the cam plate I33 slidably mounted insuitable guideways I34 in therear carriage 22. In this case, the camplate is provided with rack teethI35 which actuate the pinion I36 of avertical stub-shaft I31 which in.turn has a pinion I38 engaging a rack I39 fixed to the cross slide 29'so that longitudinal reciprocation of cam plate I33 effects directlycross slidemovement through the rack and pinion mechanism just describedin-thecross slide 29. A relative relationship of the longitudinalcarriage movement of the carriage 22 and the cross slide movement of thecross'slide 29 issimilar to that described with respect to the frontcarriage 21 and its cross slide i25 except thatLin this instance '6 ofthe rack and pinion drive :to the cross slide a greater degree of crossslide travel may @beeffected as the rear slide and tools 32 areordinarily used :for long facing cuts on the work piece;

A work cycle control cam drum :I4Il is driven synchronously with the camdrums for actuating the tool carriages and slides through gearing I4 I,142,143, and I44 having the same ratio as the gearing 89, 9I, 92, and93, so that the control cam drum Hit rotates at the same speed as thecam drums in the carriages 2i and 22. On the cam drum is the rapidtraverse control cam I45 adapted toactuate the limit switch LS-I and aspindle stop control cam I46 on the drum- I40to actuate the limit switchLS-Z to control the operation of the spindle drive motor.

Electric power for operating the lathe is derived from the usualthree-phase alternating current supply connected to the leads LI, L2,and L3, as seen in Figure 7. The control power for operating the controlmechanism is derived from leads LI and L3 connected to the primarywinding of the control transformer I41. The secondary winding of thetransformer I41 is connected to the control current'leads I48 and "I49.A pair of front and rear control stations indicated in Figure 3 areprovided on the machine, the front control station I59, Figure '8,having the spindle stop button l5I, the spindle start button E52, and aspindle jo button I 53. The front control station also'has a coolantselector switch I54 for controlling the coolant supply to the work andcutting tools. There is also provided a forward rapid traverse jogbutton I55 and a reverse rapid traverse jog button I56. The rear controlstation Iii-I has a spindle jog button I59 and a rapid traverse forwardjog button I'59-and a rapid traverse reverse jog button I60.

To start the machine, the operator presses the start button I52 toenergize relay ICR which closes contact ICRa and lCRb providing aholdingcircuit to maintain ICR energized. Closing of ICRa energizes thecontactor CP, closing power contacts CPI to energize the coolant pumpmotor I6I which drives the usual coolant pump (not shown) for supplyingcoolant to the-cutting tools and work. The coolant pump may be turnedoff and on at any time by manipulation of the selector switch I54.Closing of contact 'ICRa energizes relay AR to close contacts ARa, ARb,and ARc and open contacts ARd and AR.e. The spindle run contactor SR isthus energized to close the power contacts SRI to apply line currentfrom LI, L2, and L3 to the main spindle drive motor 33.

Contact AR of therelay AB. is provided so that after the relay AR hasbeen energized the operator cannot maintain the relay ICR energized byholding continuously down the start pushbutton I52. If this were thecase, it would interfere with the proper functioning of the limit switchLSI which would otherwise be shorted out if the operator continuouslyheld down the start button I52. Thus LSI is not interfered with so thatwhen it is actuated to stop rapid raverse itmay function properly.

.At. the beginning of the cycle, the normally closed limit switch LS'Iis closed. Whenever the switchLSI isactuatedby the dog 145, it is openedto out out rapid traverse movement of the tool slides. Thus, at thebeginning of the cycle, after the spindle motor 33 has been:energizedthe dog I45 is not contacting the limit :switchLSI so that thetraverse forward contactor TF .is energized, closing the forward rapidtraverse motor con- 17 tacts TFI .to cause rapid traverse motor I! torapidly move the tool slides and carriages up to working position.

Limit switch LS2 controls the spindle motor 33 and has control contactLS2?) which is open when the machine is in starting position of thecontrol cam drum I40. As soon as the machine is started and the rapidtraverse movement of the tools begins, the dog I46 is relieved fromactuating the limit switch LS2, allowing its contacts LS2b to close. Itwill also be noted that limit switch LS2 has a normally closed contactLS2! which opens as soon as the machine starts up in the operation cycleto de-energize the feed clutch relay FC to open contacts FCI anddeenergize the solenoid FCS to allow the feed clutch to engage totransmit feed drive power from the head stock and work spindle I4through the overrunning clutch I5 to actuate the carriages and crossslides, as described.

As rapid traverse movement of the tools continues, the cam I45 isrotated by the cam drum I40 to engage limit switch LSI, causing itsnormally closed contact LSIa to be opened as the tools approach actualcutting position. This deenergizes the traverse forward contactor TF,opening contacts TFI and de-energizing the rapid traverse motor 11. Thefeed drive then picks up through the overrunning clutch to drive thecarriages and cross slides in feeding movement.

After the actual cutting has been completed on the work piece, the limitswitch LSI is relieved from the trip dog I45 to again incite rapidtraverse movement by again re-energizing contactor TF and closingcontacts 'IFI to again cause rapid rotation of the cam drums which areso designed that continuous rotation in the same direction now effectsrapid return movement of the carriages and tool slides. As the toolsapproach return or stop position, the rapid traverse motor, spindlemotor, and automatic relay AR are deenergized by opening of LSZb. Thedog Union the cam drum I40 actuates limit switch LS2 so as to closecontact LSZa to energize the feed clutch solenoid FCS to disengage thefeed clutch BI). The contact LS2b of the limit switch LS2 is opened atthis time to de-energize the relays AR and GP to shut off the spindlemotor 33 and the coolant pump motor IEI. The spindle motor 33 is rapidlybrought to a stop by energizing the relay SP to close contacts SPImomentarily to reverse line current to the spindle drive motor 33 whichis released upon opening of the zero speed or plugging switch 34 as themotor comes to a stop in a well-known manner.

Thus, whenever the machine is in the stop position, the feed drivethrough the clutch 60 to the head stock transmission is disconnectedautomatically through the limit switch LS2 and its contact LSZa. By thisarrangement, the rapid traverse motor 11 may be readily energized foreither direction of rotation and rapid traverse of the tools. In otherwords, the rapid traversing movement of the cam drums may be reversiblyapplied, particularly for jogging the tool slides and carriages in rapidmovement for setting up the tools. This is essential so that in thereversing operation of the rapid traverse motor, the motor will not berequired to drive back through the overrunning clutch and the feed drivetrain to the work spindle and the head stock transmission, as this backdrive could not be efiiciently operated due to the great speed up fromthe rapid traverse drive motor to the head stock transmission mechanism.In other words,

reverse energization of the rapid traverse motor I'I, if the feeddisconnection was not automatically made by the clutch fill, would causethe rapid traverse motor to try to rotate the feed transmis- 'sion andhead stock gearing at an extremely high rate of speed far beyond thecapacity of power of the rapid traverse motor. Thus, no reverse rapidtraverse could be effected properly without the feed disconnection bythe clutch 60.

With this feed disconnect arrangement, the rapid traverse motor may bejogged in either direction. Forward rapid traverse movement is effectedby manipulating the rapid traverse jog buttons I55 or I59 at the frontand rear of the machine so as to energize the contactor TF to closecontacts TFI effecting forward rapid movement of the motor ll. At thesame time, relay RCR is energized to open its normally closed contactRCRa and to close contact RCRb. However, as soon as the rapid traversemotor starts up, the plugging switch 85! moves so as to energize relayFCR which opens contact FCRa and again deenergizes the rapid traverseforward relay TF to disconnect power to the rapid traverse motor. As themotor slows down toward stop, the plugging switch 85] again opensde-energizing relay FCR and allows its contact FCRa to again close andto again re-energize the forward contactor TF to again energize therapid traverse motor I! in forward movement. Thus, by continuouslyholding down the jog buttons I55 or I59, an intermittent forward joggingmotion is efiected in the rapid traverse motor for the tools.

In a similar way, pressing of the buttons I56 and I58 will efiect thereverse rapid traverse movement controlling the traverse reverse relayTR through the medium of the plugging switch 85 as in the case of theforward rapid traverse movement. There is provided a contact ARd openedwhen relay AR is energized so as to automatically cut out the operationof the rapid traverse jog buttons in either direction so that when themachine is normally operating in its automatic cycle no damage canresult and no rapid traverse movement take place in either directionshould the operator accidentally press one of the rapid traverse jogbuttons. There is thus provided an intermittent rapid traverse movementunder push button control in either direction for the tool carriages andslides. There is also associated with the control mechanism meanswhereby the feed is automatically connected to drive the tool slides andis automatically disconnected from the head stock transmission wheneverthe machine is in retracted or stopped position and reversible rapidtraversing movements are to be effected in the tool slides andcarriages. It will be noted that whenever the spindle motor 33 isenergized to drive the work spindle by energizing relays ICE and AR, thefeed clutch relay FC will be de-energized so as to automatically engagethe feed during spindle rotation.

During the normal operating cycle of the machine, the rapid traversemotor is plugged from running position to stop position by the pluggingswitch which must be set to open at or slightly above the speed at whichthe motor is normally slowly rotated during application of feed powerthrough the overrunning clutch 15 so that power will be cut off from themotor before it actually comes to a stop. This is essential, otherwisethe reverse power will be applied to the motor which will tend to backup and buck the feed drive through the overrunning clutch. Therefore,the zero speed switch actually does not open at zero speed butat a speedthe same as or slightly above thenormal slow rotation it receives whende-energized' from the feed drive.

On the reverse drive, however, the overrunning clutch does not pick upthe drive motor in feed action because the reverse rapid traversemovenection between the longitudinal'and cross slide movements of thelathe for effecting sequential operation of feed and rapid traversemovements 'to the tools together with an electric control ,mechanismadapted to effect reversible rapid traverse movementsto the slides andcarriages 'of the lathe.

There has also been provided, in connection with an electricallycontrolled feed :and rapid traverse mechanism for the machine,

an automatic arrangement for disconnecting the feed mechanism duringreversible rapid traverse jogging movements to the tool slides andcarriages.

Whilethe apparatus herein disclosed and described constitutes apreferred form of the invention, it is tobeunderstood that the apparatusis capable of mechanical alteration without departing: from the spiritof the invention and that such-mechanical arrangements and commercialadaptationsas fall within the scope of the appendantclaims are intendedto be included here Having: thus fully set forth and described thisinvention, what islclaimed as new and desired to be secured by UnitedStates Letters Patent is:

1. In a feed mechanism .for' an automatic lathe having ,a head stocktransmission, a main drive motor for driving said transmission, a workspindle driven from said transmission, and a feed transmission drivenfrom: said work spindle including a feed disconnect clutch connected tobe driven from said spindle, an overrunning clutch interconnectedbetween said feed disconnect clutch and the tool feeding mechanism ofsaid lathe, a rapid traverse drive motor operable at forward normalcutting cycle speed and reversible jogging speeds connected to said toolfee-ding mechanism, control means for simultaneously stopping said maindrive motor and operating said feed clutch to connect feed drive to saidfeeding mechanism, manually operable control means for intermittentlyreversibly jogging said rapid traverse motor and further control meansoperable to disconnect said feed clutch when said rapid traverse motoris being jogged.

2. In an automatic lathe feed mechanism including, a head stocktransmission, a main drive motor for rotating said transmission, a workspindle driven from said transmission, and a feed drive transmission forthe tool feeding devices of said lathe, the combination of a feeddisconnect clutch and an overrunning clutch serially interconnectedbetween said spindle and tool feeding devices, a rapid traverse motoroperable in forward movement for the normal feeding cycle and reversiblyoperable in jogging movements connected directly to actuate saiddevices, control means for reversibly jogging said rapid traverse motor,further control means operated by the motor operative or inoperative innormal forward feed cycle rapid traverse direction, and means foroperating said feed disconnect clutch to disconnect feed driving powerfrom said spindle to said tool feeding devices when said rapid traversemotor is being actuated in reversible jogging movements.

3. In a feed mechanism for an automatic lathe including a head stocktransmission, tool feeding devices, and a power connection to apply feedmovement to said devices from said head stock transmission, aunidirectionally operated rapid traverse motor connected to actuate saidtool feeding devices in normal cutting cycle, means for reversiblyoperating said rapid traverse motor for jogging movement of the toolfeeding devices, a plugging zero speed switch directly connected in saidmotor circuit, a feed disconnect clutch and an overrunning clutchserially interconnected between said head stock transmission and saiddevices, said zero speed switch being arranged to disconnect reversebreaking power from said motor at or above feeding speed of said toolfeeding devices when operating in one direction and to stop rapidtraverse motor reverse plugging current when said motor has been broughtto zero speed of rotation in the opposite direction.

A. In an automatic lathe feed mechanism having a head stocktransmission, a work spindle, a feed disconnect clutch driven fro-m saidspindle, an overrunning clutch driven from said feed disconnect clutch,and a tool feeding device driven from said overrunning clutch, a rapidtraverse motor connected to said tool feeding device, control meansoperable by the motion of said tool feeding device for energizing orde-energizing said rapid traverse motor in forward cutting cyclemovement, and further manually operated control means for reversiblyoperating said rapid traverse motor in jogging movements when said toolfeeding devices are in retracted position,

5. In an automatic lathe feed mechanism having a head stocktransmission, a work spindle, a feed disconnect clutch driven from saidspindle, an overrunning clutch driven from said feed disconnect clutch,and a tool feeding device driven from said overrunning clutch, a rapidtraverse motor connected to said tool feeding device, control meansoperable by the motion of said tool feeding device for energizing orde-energizing said rapid traverse motor in forward cutting cyclemovement, and further manuall operated control means for reversiblyoperating said rapid traverse motor in jogging movements when said toolfeeding device is in retracted position, including control means forautomatically disconnecting said feed disconnect clutch when said toolfeeding device is in retracted stopped position.

6. In an automatic lathe feed mechanism having a head stocktransmission, a work spindle, a feed disconnect clutch driven from saidspindle, an overrunning clutch driven from said feed disconnect clutch,and a tool feeding device driven from said over-running clutch, a rapidtraverse motor connected to said tool. feeding device, control meansoperable by the motion of said tool feeding device for energizing orde-energizing said rapid traverse motor in forward cutting cyclemovement, and further manually operated control means for reversiblyjogging said rapid traverse motor when said tool feeding devices are inretracted position, including control means for automaticallydisconnecting said feed disconnect clutch when said tool feeding devicesare in retracted stopped position, and further control means forrenderings, main drive motor for said head stock transmissioninoperative when said tool feeding devices have returned to retractedposition.

'7. In an automatic lathe feed mechanism, a head stock drive motor, ahead stock transmission driven from said motor, a work spindle drivenfrom said transmission, a feed disconnect clutch driven from saidspindle, an overrunning clutch driven from said feed disconnect clutch,a tool feeding device driven from said overrunning clutch, aunidirectionally operating rapid traverse motor directly connected todrive said tool feeding device in a cutting cycle, control means forcontrolling the operation of said head stock drive motor, said feeddisconnect clutch, and said rapid traverse motor in said unidirectionaloperation in a predetermined sequential relationship, and manuallyoperated control means for reversibly jogging said rapid traverse motor.

8. In an automatic lathe feed mechanism, a head stock drive motor, ahead stock transmission driven from said motor, a work spindle drivenfrom said transmission, a feed disconnect clutch driven from saidspindle, an overrunning clutch driven from said feed disconnect clutch,a tool feeding device driven from said overrunning clutch, a reversiblerapid traverse motor directly connected to drive said tool feedingdevice, control means for controlling the operation of said head stockdrive motor, said feed disconnect clutch, and said reversible rapidtraverse motor in a predetermined sequential relationship, including acycle control cam drum operable in timed relationship with the movementof the tool feed device, a limit switch operable by the movement of saidcam drum to predetermined positions in a work cycle to cause said rapidtraverse motor to operate in cutting cycle forward movement or stop, asecond limit switch operable by the movement of said cam drum to areturnstop position for controlling the operation of said head stock drivemotor and said feed disconnect clutch, and manually operated controlmeans for intermittently jogging said rapid traverse motor in eitherdirection.

9. In an automatic lathe feed mechanism, a main drive motor, a headstock driven from said main drive motor, a work spindle driven from saidhead stock transmission, a feed disconnect clutch driven from saidspindle, an overrunning clutch driven from said feed disconnect clutchand a tool feeding device connected to be driven from said overrunningclutch, a rapid traverse motor directly connected to drive said toolfeeding device, a control cam drum movable in timed relationship withthe movement of said tool feeding device, control means on said drum foractuating a. limit switch for applying or disconnecting forward drivingpower to said rapid traverse drive motor during the cutting cycle ofsaid tool feeding devices, a second limit switch operable by means onsaid cam drum to render said main drive motor inoperative and todisconnect said feed clutch when said tool feeding device has beenretracted to stop position, and manually operated control means forreversibly jogging said rapid traverse motor, and control meansresponsive to the position of said tool feeding devices and cam drum instop position to render said manually operated jogging means effectiveto reversibly energize said rapid traverse motor.

10. In an automatic lathe feed mechanism, a bed, a carriage movablelongitudinally on said bed, a cross slide on said carriage movabletransversely of said bed, an actuating cam drum journaled in saidcarriage, a cam on said drum connected to positively actuate said crossslide, a second cam on said drum, means including a lost motionconnection operably connecting said second cam to said bed to traversesaid carriage, and a source of feed and rapid traverse power connectedto drive said cam drum for any position of said carriage on said bed.

HAROLD J. SIEKMANN. HARRY C. KEMPER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

